Misalkan \(x = \sqrt{7\sqrt{7\sqrt{7 \dotso}}}\)
\begin{equation*}
\begin{split}
x & = \sqrt{7\sqrt{7\sqrt{7 \dotso}}} \quad {\color {red} \text{kuadratkan kedua ruas}} \\\\
x^2 & = 7 \sqrt{7\sqrt{7 \dotso}} \\\\
x^2 & = 7x \\\\
x^2 - 7x & = 0 \\\\
x(x - 7) & = 0 \\\\
x = 0 \text{ (TM) atau } x & = 7
\end{split}
\end{equation*}
